Is there a good domestic source for o'ring kits for my Contour? I have checked the websites of U.S. Brocock dealers and can't find anything listed. Ebay has a couple listed, but I am not an Ebay person. Perhaps someone has the metric size listing of them. I can source o-rings locally but I have no idea what the sizes of them are. I don't need new parts right now, but want to have them or the correct sizes on hand. I plan on keeping mine for a long time. Thanks